NEW YORK -- Maybe Eduardo Nunez plays like a Gold Glover for three months. Maybe Jayson Nix smacks 12 homers in half a season, as he did in 2009. Lots of strange things happen in a baseball season, and many of them can't be foreseen.

Derek Jeter having a significant setback, though? The Yankees should have seen that coming, and it seems they just didn't. On Thursday, it was disclosed that he has suffered a new small fracture in his surgically repaired left ankle, and will not play until sometime after the All-Star break. A team that already has a very small margin for error saw that leeway get even tinier.

"It's not what we wanted," manager Joe Girardi said. "That's for sure. ... It's something that we're going to have to fight through. Some guys are really going to have to step up in his absence."

The Yankees' faith in Jeter was understandable, in a way. For 17-plus seasons, the captain has seemed not just indestructible but entirely impervious to age, decline or any of the trappings of mere mortality.

But Jeter is 38, and it's a high-mileage 38. He's amassed nearly 12,000 big league plate appearances and nearly 22,000 innings at shortstop. His body has been through a lot. Even if this specific setback was improbable, some kind of bad news was not.

When Jeter injured his ankle in the American League Championship Series last fall, it was immediately evident that it was a major injury requiring major rehabilitation. Even as good news trickled in over the winter, with Jeter taking small steps, it was clear he was a long way from playing baseball regularly.

Now he is, once again, a long way from playing baseball regularly. Jeter will not play until at least the All-Star break, a serious blow to a Yankees team that is off to a good start but urgently needs his bat. Thus the Yanks find themselves with a Nix-Nunez job-sharing arrangement at the most important position in the infield.

The team's public stance is that that's fine. General manager Brian Cashman said that he has no plans to deviate from in-house options, and, of course, that's what he has to say.

Nix, 30, has some power, but he is a lifetime .213 hitter with a .284 on-base percentage. He's played a total of 295 innings at shortstop in his six-year big league career. Nunez, 25, is a promising offensive player who hit well in the high Minors at 22 and 23, but he is not known for his glove. He's probably an adequate or better offensive shortstop, relative to the current state of the position, but, of course, he's not Jeter.

Neither is likely to approximate Jeter's offense. Neither is likely to defend well enough to offset the offensive downgrade. In short, the Yankees have a problem at short.

As the Blue Jays have recently found out, that's not a good position to be in. There's just not much out there for a team that needs an upgrade at shortstop. There are no free agents of any real value, and not much on the trade market either.

Which is kind of how things usually go. The time to address roster deficiencies is in the offseason, or even Spring Training.

"We're going to stay as we are," Cashman said. "Those guys have done a nice job. They've earned the right, and regardless, this time of year is certainly going to be a factor in anything that happens. It's not going to be like the end of Spring Training where there might be some opportunities that become available because people only take 25 and people have [contract] outs and stuff like that. It's not the time of year you're going to see anything shake loose."

The Yankees moved to cover themselves at third base by signing Kevin Youkilis after it became clear they would do without Alex Rodriguez for a large chunk of the season. They made a series of moves to bring in options to chip in at first base, designated hitter and the outfield corners after they were hit with a rash of injuries at those positions.

But they never moved to shore themselves up at short, despite the very real possibility that a 38-year-old might not have a seamless recovery from a catastrophic ankle injury. The issue is only partly about what the options actually were, and partly the apparent lack of motivation to pursue them -- whatever they may have been.

Stephen Drew might not have taken a job with no real guarantee of playing time. Alex Gonzalez did just that, though, and he's at least a plus defender. Even someone like Tyler Greene, released by the Astros, has upside. And then there's the trade market, which might have yielded more compelling solutions in the winter than it could offer now.

Instead, the Yankees hoped. They believed in their captain. And for once, instead of being invincible, he proved himself to be an actual human baseball player, just as susceptible to injury and age as anyone else.